Dynamic response of elliptical cross‐section projectiles during penetration into concrete targets with high velocity

Abstract Elliptical‐section projectiles exhibit excellent adaptability to the flat loading spaces of aircraft platforms. Consequently, researchers have devoted more attention to elliptical cross‐sections. However, elliptical‐section projectiles exhibit a different structural response during penetration than circular‐section projectiles owing to their asymmetry. To examine the dynamic response of an elliptical cross‐section projectile during penetration into concrete, experiments were conducted using a semi‐infinite concrete target. The damage parameters of the target, penetration trajectory, deformation, and structural response characteristics of the projectile were obtained. The target resistance model was modified based on cavity expansion theory by incorporating the effects of the target crater flying dispersion and free surface attenuation. The numerical simulation method for projectile–target separation was combined with a simulation model for the penetration of an ellipsoidal cross‐section projectile into a concrete target. The penetration process of a semi‐infinite concrete target under different conditions was analyzed to determine the influence of the target parameters on the deformation and structural response of the projectile. The reliability of the simulation model was verified by comparison with the experimental results. The plastic wave propagation process, stress distribution, and equivalent plastic strain of the projectile and charge in the elliptical cross‐section were analyzed. The projectile–target separation method was verified to analyze the deformation of the elliptical projectile and the response of the charge during penetration into a concrete target. Furthermore, the section subject to fracture of the ellipsoidal projectile during the oblique penetration condition occurred in the region of 0.32–0.59 times the projectile length from the projectile nose, and in the tail region of 0.88–1.0 times the projectile length from the projectile nose. During projectile penetration into the concrete target, the stress at the nose of the charge was observed to be the greatest. Furthermore, an increasing distribution of the shear stress was evident from the axis to the edge of the charge, whereas a decreasing distribution pattern was evident from the nose to the end.